Staging: otus: fix some sparse warnings

*apdbg.c: use NULL pointer instead of 0 interger. Also make two functions private.
Signed-off-by: Thiago Farina <tfransosi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/otus/apdbg.c

@@ -90,8 +90,27 @@ struct zdap_ioctl {
 
 #endif
 
-char hex(char);
-unsigned char asctohex(char *str);
+static char hex(char v)
+{
+	if (isdigit(v))
+		return v - '0';
+	else if (isxdigit(v))
+		return tolower(v) - 'a' + 10;
+	else
+		return 0;
+}
+
+static unsigned char asctohex(char *str)
+{
+	unsigned char value;
+
+	value = hex(*str) & 0x0f;
+	value = value << 4;
+	str++;
+	value |= hex(*str) & 0x0f;
+
+	return value;
+}
 
 char *prgname;
 
@@ -109,7 +128,7 @@ int set_ioctl(int sock, struct ifreq *req)
 
 int read_reg(int sock, struct ifreq *req)
 {
-	struct zdap_ioctl *zdreq = 0;
+	struct zdap_ioctl *zdreq = NULL;
 
 	if (!set_ioctl(sock, req))
 		return -1;
@@ -125,7 +144,7 @@ int read_reg(int sock, struct ifreq *req)
 
 int read_mem(int sock, struct ifreq *req)
 {
-	struct zdap_ioctl *zdreq = 0;
+	struct zdap_ioctl *zdreq = NULL;
 	int i;
 
 	if (!set_ioctl(sock, req))
@@ -380,25 +399,3 @@ int main(int argc, char **argv)
 	exit(0);
 }
 
-unsigned char asctohex(char *str)
-{
-	unsigned char value;
-
-	value = hex(*str) & 0x0f;
-	value = value << 4;
-	str++;
-	value |= hex(*str) & 0x0f;
-
-	return value;
-}
-
-char hex(char v)
-{
-	if (isdigit(v))
-		return v - '0';
-	else if (isxdigit(v))
-		return tolower(v) - 'a' + 10;
-	else
-		return 0;
-}
-